Logic computing

Abstract

A spin wave control device includes a first magnetic layer, a second magnetic layer arranged above the first magnetic layer, and a capping layer overlapping a portion of the second magnetic layer. The first magnetic layer has a magnetization pointing in a first direction and the second magnetic layer has a magnetization pointing in a second direction that is approximately opposite to the first direction. The capping layer has a magnetization pointing approximately in the first direction or approximately in the second direction.

What is claimed is: 
     
         1 . A spin wave control device comprising:
 a first magnetic layer having a magnetization pointing in a first direction;   a second magnetic layer arranged above the first magnetic layer and having a magnetization pointing in a second direction that is approximately opposite to the first direction; and   a capping layer overlapping a portion of the second magnetic layer or a portion of the first magnetic layer, the capping layer having a magnetization pointing approximately in the first direction or approximately in the second direction.   
     
     
         2 . The device of  claim 1 , further comprising:
 a first spacer layer sandwiched between the first magnetic layer and the second magnetic layer; and   a second spacer layer sandwiched between the second magnetic layer and the capping layer.   
     
     
         3 . The device of  claim 2 , wherein the capping layer is configured to rotate a polarization of a polarized spin wave injected into the spin wave control device. 
     
     
         4 . The device of  claim 3 , wherein a rotation direction of the polarization of the polarized spin wave depends on a direction of the magnetization of the capping layer. 
     
     
         5 . The device of  claim 4 , wherein a rotation angle of the polarization of the polarized spin wave depends on at least one of a length of the capping layer, a thickness of the first spacer layer, a thickness of the second spacer layer, a frequency of the polarized spin wave, or material properties of the first magnetic layer and the second magnetic layer, a length direction of the capping layer being approximately parallel to a propagation direction of the polarized spin wave in the spin wave control device. 
     
     
         6 . The device of  claim 1 , wherein a direction of the magnetization of the capping layer is configured to switch between aligning approximately with the first direction and aligning approximately with the second direction. 
     
     
         7 . The device of  claim 6 , further comprising:
 a switching device coupled to the capping layer and configured to switch the direction of the magnetization of the capping layer.   
     
     
         8 . The device of  claim 1 , wherein the first direction and the second direction are approximately perpendicular to an upper surface of the second magnetic layer or approximately perpendicular to a side surface of the second magnetic layer. 
     
     
         9 . The device of  claim 1 , wherein:
 the first magnetic layer and the second magnetic layer include a same material or a same structure; and   a total magnetization of the first magnetic layer is same as a total magnetization of the second magnetic layer.   
     
     
         10 . A method for controlling a polarized spin wave comprising:
 injecting the polarized spin wave into a synthetic antiferromagnet (SyAF); and   controlling a magnetization direction of a capping layer overlapping a portion of the SyAF to rotate a polarization of the polarized spin wave.   
     
     
         11 . The method of  claim 10 , wherein:
 the SyAF includes:
 a first magnetic layer having a magnetization pointing in a first direction; 
 a second magnetic layer arranged above the first magnetic layer and having a magnetization pointing in a second direction that is approximately opposite to the first direction; and 
   controlling the magnetization direction of the capping layer to rotate the polarization of the polarized spin wave includes:
 controlling the magnetization direction of the capping layer to align approximately with the first direction to cause the polarization of the polarized spin wave to be rotated in a first rotation direction; or 
 controlling the magnetization direction of the capping layer to align approximately with the second direction to cause the polarization of the polarized spin wave to be rotated in a second rotation direction, the second rotation direction being opposite to the first rotation direction. 
   
     
     
         12 . A computing device comprising:
 a logic track including two logic-track magnetic domains separated by a logic-track domain wall;   an input track arranged crossing the logic track at a first position of the logic track, the input track including at least one input-track magnetic domain, and each of the at least one input-track magnetic domain including at least one input-track storage unit configured to store binary 0 or 1; and   an output track arranged crossing the logic track at a second position of the logic track near the logic-track domain wall, the output track including at least one output-track magnetic domain, and each of the at least one output-track magnetic domain including at least one output-track storage unit configured to store binary 0 or 1.   
     
     
         13 . The device of  claim 12 , wherein the logic track includes:
 a first magnetic layer including:
 a first magnetic section in a first one of the two logic-track magnetic domains, a magnetization of the first magnetic section pointing in a first direction; and 
 a second magnetic section in a second one of the two logic-track magnetic domains, a magnetization of the second magnetic section pointing in a second direction approximately opposite to the first direction; and 
   a second magnetic layer arranged above the first magnetic layer and including:
 a third magnetic section in the first one of the two logic-track magnetic domains, a magnetization of the third magnetic section pointing in the second direction; and 
 a fourth magnetic section in the second one of the two logic-track magnetic domains, a magnetization of the fourth magnetic section pointing in the first direction. 
   
     
     
         14 . The device of  claim 13 , wherein a magnetization of each of the at least one input-track magnetic domain points approximately in the first direction or approximately in the second direction. 
     
     
         15 . The device of  claim 12 , wherein a position of the logic-track domain wall is located at an interface between the two logic-track magnetic domains. 
     
     
         16 . The device of  claim 12 , wherein the input track and the output track are approximately perpendicular to the logic track. 
     
     
         17 . The device of  claim 12 , further comprising:
 an input-track driving device coupled to the input track and configured to drive one of the at least one input-track storage unit into and out of an overlapping section of the input track, the overlapping section of the input track being a section of the input track that overlaps the logic track; and   an output-track driving device coupled to the output track and configured to drive one of the at least one output-track storage unit out of an overlapping section of the output track, the overlapping section of the output track being a section of the output track that overlaps the logic track.   
     
     
         18 . The device of  claim 12 , wherein the first position is closer to a spin wave injecting end of the logic track than the second position. 
     
     
         19 . The device of  claim 18 , further comprising:
 an instruction track arranged crossing the logic track, the instruction track being configured to change a polarization direction of a spin wave injected from the spin wave injecting end.   
     
     
         20 . The device of  claim 19 , wherein the instruction track is arranged approximately perpendicular to the logic track.